A Meta-Analysis of Neuropsychological Outcome After Mild Traumatic Brain Injury: Re-analyses and Reconsiderations of Binder et al. (1997), Frencham et al. (2005), and Pertab et al. (2009)

Abstract

The meta-analytic findings of Binder et al. (1997) and Frencham et al. (2005) showed that the neuropsychological effect of mild traumatic brain injury (mTBI) was negligible in adults by 3 months post injury. Pertab et al. (2009) reported that verbal paired associates, coding tasks, and digit span yielded significant differences between mTBI and control groups. We re-analyzed data from the 25 studies used in the prior meta-analyses, correcting statistical and methodological limitations of previous efforts, and analyzed the chronicity data by discrete epochs. Three months post injury the effect size of -0.07 was not statistically different from zero and similar to that which has been found in several other meta-analyses (Belanger et al., 2005; Schretlen & Shapiro, 2003). The effect size 7 days post injury was -0.39. The effect of mTBI immediately post injury was largest on Verbal and Visual Memory domains. However, 3 months post injury all domains improved to show non-significant effect sizes. These findings indicate that mTBI has an initial small effect on neuropsychological functioning that dissipates quickly. The evidence of recovery in the present meta-analysis is consistent with previous conclusions of both Binder et al. and Frencham et al. Our findings may not apply to people with a history of multiple concussions or complicated mTBIs.

Neuropsychological Outcomes of U.S. Veterans with Report of Remote Blast-Related Concussion and Current Psychopathology

“…Consistent with previous research suggesting a time-limited course of impairment following conventional concussive injuries (cf. Rohling et al, 2011), present results suggest that BRC does not in and of itself contribute to cognitive impairment months or years following injury. Veterans with remote histories of BRC should anticipate favorable long-term cognitive prognosis.…”

“…Indeed, results of at least one longitudinal study of OEF/OIF cohorts suggest that the deployment process itself may be associated with cognitive limitations (Vasterling et al, 2006). Additionally, comparison of an OEF/OIF concussion sample with an OEF/OIF non-concussion sample will allow for direct examination of long-term impairments that may be associated with BRC, or alternatively define whether outcomes mimic favorable long-term outcomes reported in civilian concussion samples (Belanger, Curtiss, Demery, Lebowitz, & Vanderploeg, 2005;Frencham, Fox, & Maybery, 2005;Iverson, 2005;McCrea et al, 2005;Rohling et al, 2011;Schretlen & Shapiro, 2003). Results of the latter studies suggest that cognitive impairment associated with concussion is time-limited; the great majority of individuals attain baseline function within days, weeks, to no more than a few months post-injury.…”

The neuropsychological outcomes of concussion: A systematic review of meta-analyses on the cognitive sequelae of mild traumatic brain injury.

“…The sample size (N) of mTBI (range: 264 -3,801) and control participants (range: 176 -5,631) fluctuated across quantitative reviews. Among the limited studies reporting demographics of their samples (i.e., Broglio & Puetz, 2008;Frencham et al, 2005;Rohling et al, 2011;Zakzanis et al, 1999), mean reported age (range: 19 -35) and percent of male participants (range: 64 -92.9) differed considerably across reviews. Notably, the only sports-related mTBI metaanalysis reporting sample demographics involved the youngest and most male sample (Broglio & Puetz, 2008).…”

“…Despite the prevalence and public concern surrounding mTBI, past researchers have dismissed its long-term neuropsychological impact as clinically insignificant Frencham, Fox, & Maybery, 2005;Larrabee, Binder, Rohling, & Ploetz, 2013;Rohling et al, 2011; Shretlen & Shapiro, 2003); however, some individuals may remain symptomatic long after the concussive event (Bigler et al, 2013;Pertab, James, & Bigler, 2009), potentially explained by acute neurological impairment that can persists after injury (e.g., Cohen et al, 2007;Holli et al, 2010). Alternatively, some researchers have identified more psychogenic predictors of persistent symptoms (Silverberg & Iverson, 2011).Persistent symptoms of mTBI remain a contentious issue, with a recent scholarly dialogue closely examining the evidence both for and against their existence (Bigler et al, 2013;Larrabee et al, 2013;Pertab et al, 2009;Rohling et al, 2011). Dating back to the 19th century, scholars have argued between the psychological and physiological etiologies of post-mTBI symptoms (see Binder et al, 1997).…”

Treatment for depression following mild traumatic brain injury in adults: A meta-analysis

“…The majority (up to 90%) of TBIs are mild (Langlois, Keglar et al 2003;Langlois, Rutland-Brown et al 2006), and while most cases recover fully within three months (Rohling, Binder et al 2011), a significant proportion report on-going difficulties. Depression is the most commonly reported psychiatric consequence of TBI, with reports suggesting that up to 60% of patients with TBI develop depression within 12 months of injury, even following a mild injury (Busch 1998;Hibbard, Uysal et al 1998;Fann, Uomoto et al 2000;Robinson and Jorge 2005;Hoge 2008).…”